Tensile testing-machine test rate

Strain curve is provided. They can be programmed to be extremely useful in quality control. See testing, tensile testing-machine test rate The speed at which its cross-head moves. An increase in strain rate typically results in an increasing yield point and strength. Test methods specify speed of testing for the different materials (soft to rigid) to be tested since test results can be affected by the time-dependent factor. 

The principal type of shear test specimen used in the industry, the lap shear specimen, is 2.54 cm wide and has a 3.23-cm overlap bonded by the adhesive. Adherends are chosen according to the industry aluminum for aerospace, steel for automotive, and wood for constmction appHcations. Adhesive joints made in this fashion are tested to failure in a tensile testing machine. The temperature of test, as weU as the rate of extension, are specified. Results are presented in units of pressure, where the area of the adhesive bond is considered to be the area over which the force is appHed. Although the 3.23-cm ... 

Peel tests are accompHshed using many different geometries. In the simplest peel test, the T-peel test, the adherends are identical in size, shape, and thickness. Adherends are attached at thek ends to a tensile testing machine and then separated in a "T" fashion. The temperature of the test, as well as the rate of adherend separation, is specified. The force requked to open the adhesive bond is measured and the results are reported in terms of newtons per meter (pounds per inch, ppi). There are many other peel test configurations, each dependent upon the adhesive appHcation. Such tests are well described in the ASTM hterature. 

Test rate and property The test rate or cross-head rate is the speed at which the movable cross-member of a testing machine moves in relation to the fixed cross-member. The speed of such tests is typically reported in cm/min. (in./min.). An increase in strain rate typically results in an increase yield point and ultimate strength. Figure 2-14 provides examples of the different test rates and temperatures on basic tensile stress-strain behaviors of plastics where (a) is at different testing rates per ASTM D 638 for a polycarbonate, (b) is the effects of tensile test-... 

The light intensity of the 3000 A lamps was determined as previously described ( ). Yarn samples were knit on a Lawson Fiber Analysis Knitter (FAK), and yarn tensile testing was performed on an Instron Model 1101 (TM-M) constant rate of extension testing machine. 

A series of six stress-strain cycles with a crosshead rate of 600 mm/min was applied to specimens having a parallel length of 25 mm and a cross-section of 1 x 4 mm2 on a tensile testing machine. The samples were continuously stretched in six hysteresis cycles up to 60% of their elongation at break values, as shown in Fig. 47. This procedure is an established one and widely practiced for elastomeric composites reinforced with fillers such as carbon black and silica, which tend to build a strong filler-filler network [83]. 

Tensile tests involve either stretching a sample and monitoring the load or loading it while monitoring the extension. The simplest test uses a tensile testing machine (e.g. an Instron) where the sample is stretched at a constant rate while the load is measured using a (usually hard) load cell. Variations on this test allow the specimen to be extended at a constant strain rate or to be loaded at a constant load, or stress rate. These latter tests are usually carried out on servo hydraulic machines. 

All these tests are in common use to measure the tensile stiffness of polymers. For example, tests at constant extension rate are often carried out on an Instron tensile testing machine. Tensile creep is used in many cases while stress relaxation is not so common. Dynamic testing is commonly performed using the Rheovibron or other commercial equipment32 or home made equipment33,... 

ASTM D 4964 Standard Test Method for Tension and Elongation of Elastic Fabrics (Constant-Rate-of-Extension Type Tensile Testing Machine)... 

Another suitable method for evaluating elastomeric finishes is ASTM D 4964-96 Standard Test Method for Tension and Elongation of Elastic Fabrics (Constant-Rate-of-Extension Type Tensile Testing Machine) . Fabric samples are formed into loops and are placed through several extension-recovery cycles under controlled conditions. Table 12.2 shows an overview of test methods for elastomeric finishes. 

Four point bending tests are used to investigate the evolution of the toughness with the loading rate for the two materials (see Fig.l and table 1). We used an Instron servohydraulic tensile test machine in which a force rate was prescribed from 12N/mn to 5200N/mn. We choose to represent the influence of the loading rate with the variable Kj which is derived from Eq. 3. The stress rate CTq is then involved and estimated from the prescribed force rate. This variable K j is preferred to the prescribed force rate to provide data for the material fracture under mode... 

Uniaxial tensile tests were carried out to determine the stress-strain curves and document the damage growth on a computer-controlled Instron model 8516 servo hydraulic testing machine operating at a strain rate of 5% min . The macroscopic tensile yield stress was considered equal to the maximum stress on the loading curve. The Young s modulus was determined as the plateau value of a plot of the secant modulus as a function of the strain. 

The plastic strains are measured by means of point marking method. The markings with 1 mm interval in a direction of tensile axis were made by a micro-vickers hardness tester before tensile tests. Tensile tests were conducted at room temperature at a cross-head rate of 0.5 mm/min with an Instron-type testing machine. After the tensile deformation, the relative displacements between markings were measured under a precision machinery microscope, and the corresponding local strains in the direction of tensile axis were calculated. Then deformed specimens were cut into pieces of 1 mm width by a low speed cutter perpendicular to the tensile axis. The saturation magnetization of each piece was measured by magnetic balance at room temperature. 

Flat samples with a gauge size of 6x3x2 mm3 were tensile tested using a Shimadzu AG-G machine in the temperature interval 350-525°C and at strain rates ranging from 1.4xl0"3 to 1.4xl0 1 s 1. The strain rate sensitivity coefficient, m, was determined from the slope of the log o vs. log e curves. 

Tensile and compressive tests were performed at room temperature with a tensile testing machine (DY25, Adamel-Lhomargy). For the tensile tests, strain measurements were performed with an extensometer (EX-10) at a strain rate of 3.3 x 10-4 s-1, using ISO-60 standard specimens. Samples of dimension 20 x 12 x 6 mm were deformed in a compression cage between polished steel plates. The nominal strain was determined by averaging the results from two linear variable differential transformer (LVDT) transducers. The strain rate used was 8.3 x 10"4 s-1. 

In this test, a strip of separator (25 x 150mm) is clamped in a tensile testing machine. The rate of jaw separation is set at 25 5 mm per min and the breaking force is recorded. 

The shear strength measurement was conducted with an Instron tensile test machine of the constant-rate-of-crosshead movement type. A shear tool described in ASTM D732 was used. The samples were run at a crosshead speed of 0.05 In/mln. 

ASTM D5735. 1995, Tearing strength of non woven fabrics by the tongue (single rip) procedure (constant-rate-of-extension tensile testing machine),... 

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